In the handling of sewage especially on boats and recreational vehicles, sewage is typically transported from a toilet (e.g., utilizing a vacuum pump) to a sewage holding tank, which is emptied at a suitable location where it can be handled and in an environmentally-responsible manner. Sometimes it is desirable to move the holding tank, disconnect the sewage hose or other conduit coming from the toilet, or repair or replace components of the system. While one way that this could be effected is to provide a plurality of valves connecting the holding tank to a sewage conduit, for example, one then has the expense of two or more valves, and the operation of the two or more valves is required to open or shut down the system.
According to the present invention, a system, and a valve that is ideally suited for the system (although it is useful in other contexts too), are provided which allow ready disconnection of a conduit in a holding tank (or other fluid conducting or retaining components) so that both are sealed from the environment, utilizing a single valve actuator.
According to one aspect of the present invention, a valve is provided comprising: An outer casing including a first connecting part for connection to a first fluid transporting or retaining component, and a second connecting part distinct from but mating with the first connecting part, and for connection to a second fluid transporting or retaining component. First and second inner movable valve elements movable from an open position allowing flow of fluid from a first fluid transporting or retaining component to a second fluid transporting or retaining component, and a closed position in which fluid cannot flow between first and second fluid transporting or retaining components, the inner elements when in the closed position allowing disassembly of the first connecting part from the second connecting part without either of the first and second fluid transporting or retaining components communicating with the surrounding environment at the valve.
First and second stationary seals may act between the outer casing and the movable valve element. The first seal may be disposed adjacent the connection of the conduit to the outer casing, the second seal opposite the first seal from the outer casing and in alignment with the first seal.
The outer casing first and second parts each comprise a circular cross section hollow cylinder having an axis of elongation, the first end substantially perpendicular to the axis of elongation, and the second end forming an oval surface disposed at an angle significantly less than 90.degree. (preferably about 35.degree.-55.degree.) with respect to the axis of elongation. The oval surfaces of the outer casing parts are in face-to-face engagement with each other. The first outer casing part second end is typically open, and the second outer casing part second end is typically closed.
The first and second movable valve elements comprise a circular cross section hollow cylinder having a sidewall and an axis of elongation, the first end substantially perpendicular to the axis of elongation, and a second end forming an oval surface disposed at an angle significantly less than 90.degree. (typically about 35.degree.-55.degree.) with respect to the angle of elongation. The oval surfaces of the first and second movable valve element are in face-to-face engagement with each other. The first movable element has a solid sidewall and open second end, and the second element has an open second end and an opening in the sidewall for cooperation with tile first fluid conducting or retaining component, while the open first end communicates with the second fluid conducting or retaining component when the movable valve elements are in the open position.
The first and second movable valve elements are mounted in the outer casing for rotation about an axis of rotation aligned with the axis of elongation of the cylinders forming the valve elements. An actuator is typically provided adjacent the first end of the first movable valve element, and the first end of the first outer casing has an opening therein through which the actuator extends (into contact with the first movable valve element). A vent may be provided in an overlapping area of the valve elements.
According to another aspect of the present invention a valve per se is provided. The valve comprises the following elements: an outer casing including a first connecting part for connection to a first fluid transporting or retaining component, and a second connecting part distinct from but mating with the first connecting part, and for connection to a second fluid transporting or retaining component. First and second inner movable valve elements movable from an open position allowing flow of fluid from a first fluid transporting or retaining component to a second fluid transporting or retaining component, and a closed position in which fluid cannot flow between first and second fluid transporting or retaining components. The outer casing first and second parts each comprise a circular cross section hollow cylinder having an axis of elongation, a first end substantially perpendicular to the axis of elongation, and a second end forming an oval surface disposed at an angle of significantly less than ninety degrees with respect to the axis of elongation, the oval surfaces being in face-to-face engagement with each other. The first outer casing part second end is open and the second outer casing part second end is closed. The first and second movable valve elements each comprise a circular cross section hollow cylinder having a sidewall and an axis of elongation, a first end substantially perpendicular to the axis of elongation and a second end forming an oval surface disposed at an angle significantly less than 90 degrees with respect to the axis of elongation; the oval surfaces of the first and second movable valve elements in face-to-face engagement with each other; the first movable valve element having a solid sidewall and open second end, and the second element having an open second end and an opening in the sidewall for cooperation with the first fluid conducting or retaining component while the open first end communicates with the second fluid conducting or retaining component when the movable valve elements are in the open position.
The invention also relates to a sewage handling system comprising at least one toilet, a sewage holding tank having a sewage receiving opening therein, and a conduit operatively connected to the at least one toilet (e.g., through a vacuum pump). The conduit comprises the first fluid transporting or retaining component as described above, and the holding tank the second.
Various indicia may also be provided on the components--for example, on the actuator and on a seal-containing projection opposite the connection of the conduit to the outer casing--for indicating when the valve is in the closed position, and therefore, that the components can be disassembled. Alternatively, seals may be provided on a movable element instead of associated with the outer casing, if the proper quality of sealing material can be used economically for the intended environment.
It is a primary object of the present invention to provide an improved sewage handling system, and a valve ideally suited for use in such a system, but also suitable for other purposes. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.